The invention relates to improvements in methods of and in apparatus for supplying discrete commodities to consuming or processing machines. More specifically, the invention relates to improvements in methods and apparatus which can be resorted to for the supplying of sets (e.g., stacks) of blanks to machines wherein groups (e.g., arrays of twenty) rod-shaped articles of the tobacco processing industry are introduced into and sealed in packets. Typical examples of packets which are presently in use for the confinement of arrays of rod-shaped articles of the tobacco processing industry (such as plain or filter cigarettes and hereinafter called cigarettes for short) are so-called hinged-lid packets or packs.
Heretofore known apparatus for supplying stacks of blanks to packing machines for conversion into packets which sealingly confine arrays of cigarettes often employ a first conveyor which delivers stacks of blanks from a source to a first station, a second conveyor which advances stacks from a second station to the packing machine, and a third conveyor which transports stacks from the first station to the second station. A drawback of heretofore known methods and apparatus is that they are not sufficiently reliable to ensure predictable feeding of stacks of blanks to modern high-speed cigarette packing machines. Predictable delivery of blanks is particularly important when the machines are designed to turn out large numbers of packets per unit of time. If the blanks are to be converted into hinged-lid packets, they are normally stored in a magazine of rather limited capacity because the space is at a premium in the halls of plants wherein cigarettes are confined in hinged-lid packets and/or other types of receptacles. Since the magazines are relatively small, they must be refilled either continuously or at frequent intervals. This necessitates the establishment of paths between the magazines of discrete packing machines and a main magazine or reservoir which is designed to contain a large supply of blanks.
U.S. Pat. No. 5,183,380 discloses an apparatus which is designed to supply stacks of blanks to a cigarette packing machine and employs means for transferring stacks of blanks from pallets to a magazine of the packing machine. The transferring means includes and endless horizontal conveyor which is provided with pockets for reception and temporary confinement of stacks of blanks between a pallet and the magazine of the respective packing machine. A further conveyor is provided to transfer stacks from a pallet into successive pockets of the endless horizontal conveyor. The stacks in the pockets form a row which extends from the further conveyor to the magazine when the operation of the patented apparatus is proper. The failure of the further conveyor to deliver a stack into each and every oncoming pocket of the endless horizontal conveyor is likely to entail, or invariably results in, an interruption of normal delivery of stacks from the magazine into the packing machine. This can result in lengthy interruptions of the operation of the packing machine or in a reduction of the speed of the packing machine with attendant huge losses in output.
To the extent that it can be considered as contributing to the understanding of the present invention, the disclosure of the U.S. Pat. No. 5,183,380 to Focke et al. is incorporated herein by reference.